How to pick a display? So many factors

I have been working on a project that involves creating my own PCB with an STM32 MC and other peripherals.
Context: I am wanting to prototype and then slap things into Altium to eventually have a working PCB. Displays have been a particular rough spot for several reasons:

  • Drivers/communication protocols: I can’t find a good guide that helps me understand displays that are compatible or good for a specific MC (STM32F103RB) or task.
  • Power requirements: some displays require 3.3V and some 5V forcing some redesigns.
  • Connectivity: I am unfamiliar with a lot of connector types which has made breadboarding with these displays difficult.
  • Specifications: A lot of displays are geared towards arduinos and raspis which usually are more plug-and-play with minimal guides regarding STM32s.

Here are the specs that I need:

  • 2.4" +
  • Connectors compatible for breadboarding
  • Responsive/fast refresh rates
  • Prefer non-color
  • Non-touchscreen
  • Works with STM32

I feel that these specs are not too difficult yet I am find guides regarding displays and STM32s.

Thanks for any help I can get.

Greetings,

Perhaps the first thing to do would be calibrate one’s expectations.

The last 10-15 years have seen a great proliferation of hardware products and software resources that allow many details of the actual technology to be swept under the rug and ignored by folks who don’t want to concern themselves with those details.

Similar to the way that the frozen pizza section at the grocery store enables most anybody to “make” a pizza with almost no effort, study, or understanding of how pizzas end up in the freezer case, these resources enable people to realize functions that are in actuality quite complex with minimal effort.

While there might be a decent selection of frozen pizzas to choose from, they’re fundamentally pre-defined and limited in variety compared to what one can obtain if one learns how to make a pizza from basic ingredients.

Understand that while there are evaluation and demo boards available for the STM32 product family, the term is fundamentally a reference to a line of general-purpose microcontrollers that spans roughly a 10x range of performance potential with nearly 4000 active part numbers available.

In contrast, “Arduino” and “Raspberry Pi” are references to pre-defined hardware platforms and software ecosystems based on a relatively limited number of physical devices, enabling an awful lot of messy details to get neatly packaged and abstracted away. To say you want to use an “STM32” is thus analogous to saying you want to “make” a pizza in the sense of mixing dough, simmering tomatoes into a sauce, grating cheese etc. as opposed to “making” a pizza by putting something that came out of a box into a warm oven.

All that said, putting “display” into the DK search bar summons the following top results:


The “graphic” displays are ones which provide a generic free-form pixel field to light up as one wishes, whereas the “character and numeric” sort are those geared toward the presentation of pre-defined characters. Both are more of the ‘flour and tomato’ sort of products. Under “expansion boards, daughter cards” one finds items more analagous to the frozen pizza concept with friendlier connectorization etc.

Ultimately, what exactly one has in mind when asking for a display that “works with STM32” is a rather important question. As a general-purpose microcontroller one could conceivably hitch it up to most any display one cared to, given sufficient effort and some additional components. If one’s looking for a solution that comes with step-by step instructions and can be ready in 30 minutes or less, the options are going to be a lot more limited.

ST partnered with Segger for use of STemWin on STM32 family of parts:

https://www.st.com/en/partner-products-and-services/segger-emwin.html

In this PDF, ST outlines a number of supported LCD controllers:

PDF: https://www.st.com/resource/en/application_note/an4323-getting-started-with-stemwin-library-stmicroelectronics.pdf

Regards,